Formamide → 6-chlorothieno[3,2-d]pyrimidin-4(3H)-one

Temperature

205 °C

In a 50 ml round bottom flask equipped with a mechanical stirrer and a reflux condenser, a mixture of 7.0 g (0.036 mole) of methyl 3-amino-5-chloro-2-thiophenecarboxylate and 15 ml of formamide was heated at 205° C. for 7 hours. Upon cooling to room temperature, the reaction solution afforded a precipitate which was filtered: yield about 3.3 g. The crude tan solid was taken up in hot methanol, treated with activated carbon, and filtered. Upon cooling to room temperature, the filtrate afforded yellow crystals of 6-chlorothieno[3,2-d]pyrimidin-4(3H)-one: m.p. 238°-239° C.; yield 2.5 g (36%); ir (KBr) 3427 cm-1, 1688, 1659, 1600, 1510, 1476, 1410 among others; 1H-nmr (CDCl3 +some trifluoroacetic acid) delta 7.5 ppm (s, 1H), 9.1 (s, 1H); mass spectrum 186 (molecular ion and parent peak with the expected isotope pattern), 159 (-27), 131 and others.

1. customIn a 50 ml round bottom flask equipped with a mechanical stirrer and a reflux condenser
2. temperatureUpon cooling to room temperature
3. customthe reaction solution afforded a precipitate which
4. filtrationwas filtered
5. additiontreated with activated carbon
6. filtrationfiltered
7. temperatureUpon cooling to room temperature

ORD record

ord-3d47ed57a50c4a52a4de07c285b23e88

Source dataset

uspto-grants-1989_01

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04797486